Improvement in hinxbs



Ciniieii einen @anni (emite,

JOHN PLANT, OF WASHINGTON, DISTRICT OF COLUMBIA.

Letters Patent No. 106,278, dated August 9, 1870.v

I IMPROVEMENT mi mees.

The Schedule referred to iu these Lettera Patent and making part of the same.

To whom it may concern.`-

Be itknown that I, JOHN PLANT, ofthe city of Washington, Dist-riet of Columbia, have invented an Improved ShutterHingef and I do declare the following to be anlexaet description thereof, reference being had to the accompanying drawing, andto'the letters ot reference marked thereon, making a part of' this specification, in which- Figure 1 represents a front View of the hinge;

Figure 2 shows the top edge of' the same;

Figure 3 shows one of the ends at the joint;

' Figures 4 and 5 show the center or joint when separated; and v Figure 5 shows, by the dotted lines, how the oppositeside of the hinge raises and lowers on the pivot as the shatter is opened or closed.

The nature of my invention consists in the doubleaeting spirals at both the upper and lowersides of the joints, so that one side always raises or lower the shutter to open and close it, and holds it in `its position firmly and securely when opened or closed. These spirals or sections of a. screw vare cast solid iwith the hinge, and form an entirely novel hinge. V

To enable others skilled in the artto make and use my invent-ion, I. will proceed to describe it as follows: A represents the pivot upon which the hinge turns, solid with the lower cylinder B, but 'operating in the hollow cylinder, O, above..

At the upper and lower ends of these oylinders B and C are the spirals D D, the front part-having a flanged edge, 1*),and rounding on each side of the`A ange.. 1

The back side of the hinge is perfectly even and straight.

The offset- G is an inclined plane, upon .which the flange operates and rises until the shuttle is open, when the hinge falls again on the pivot Ato its place, resting on the pivot, while the angular ends of each plate, at H, brace the `ioint firmly, as the angular' ends J of the spirals tit against the angle'or inclined plane offset H, holding the shutter open and square with the hinge, keeping the shuttersecurely in its open position, and relieving the straitl on the pivot common .to other hinges. l

What I claim as my invention, and desire to secure by Letters Patent, is-

The combination of thetwo spirals D D, cast upon the leaves of t-he hinge beyond. the pintle-sockets, with 'the inclinesJ J, for catching upon the corresponding inclines G G, the said spirals always resting upon the inclines, to reiieve the pintle of strain, all arranged as 'and for thepurpose'deseribed.

. JOHN PLANT.

Witnesses:

J. FRANKLIN REIGART, EDM. F. BROWN. 

